This invention relates to switchable power combiners and power dividers of the type described in prior application Ser. No. 09/896,171, filed Jun. 29, 2001, which is assigned to the same assignee as the present application. The specification of the prior application is incorporated herein by reference as if fully set forth herein.
The power divider/combiner described in the referenced and incorporated prior application is useable in connection with power amplifiers as described therein. It becomes desirable in some applications to provide increased power handling capacity for RF signals, particularly in power combining applications, wherein the device is arranged to combine the outputs of multiple power amplifiers. The present invention relates to improvements of the power divider/combiner described in the above application for purposes of handling higher average signal power.
While power dividers and combiners are substantially the same in construction, the present invention is most applicable in the case of a power combiner for applications wherein the signal outputs from high power amplifiers are combined, and accordingly in the combiner application higher signal handling power is required.
It is an object of the present invention to provide a high power switchable power combiner which has the capability of handling higher signal power levels.
In accordance with the invention there is provided a high power switchable power combiner. The combiner includes a first plurality of at least three input ports for receiving signals to be combined. There is provided a transmission line having a center conductor and connected to an output port for providing output combined signals. A first plurality of switching members is provided, one for each of the input ports. Each of the switching members is moveable between a first position connecting the center conductor and a corresponding one of the input ports and a second position wherein the center conductor is disconnected from the corresponding input port. At least two switchable matching elements are provided. Each of the switchable matching elements is moveable between a first position connected to the center conductor at a selected location on the center conductor and a second position disconnected from the center conductor. The configuration of the matching elements and the selected location on the center conductor is selected to cause a first of the matching elements when in the first position to provide an impedance match for the switchable power combiner, when two of the first plurality of switching members are in the first position, and to cause a combination of two or more of the matching elements in the first position to provide an impedance match for the switchable power combiner when three or more of the first plurality of switching elements are in the first position.
In accordance with the invention there is provided a high power switchable power combiner which includes a first plurality of at least two input ports for receiving signals to be combined. There is provided a transmission line having a center conductor arranged between first and second conductive housing members and connected to an output port for providing output combined signals. A first plurality of switching members is provided one for each of the input ports. Each of the switching members is moveable between a first position connecting a first end portion of the center conductor and a corresponding one of the input ports and a second position wherein the center conductor is disconnected from the corresponding input port. There is provided at least one switchable matching element which is moveable between a first position, connected to the center conductor at a selected location thereon with respect to the first end portion, and a second position, disconnected from the center conductor. At least one thermally conductive dielectric member is arranged between the center conductor and one of the conductive housing members in at least the region of the center conductor between the first end portion and the selected location. The thermally conductive dielectric member is mechanically compressed between the center conductor and the conductive housing member.
For a better understanding of the present invention, together with other and further objects, reference is made to the following description, taken in conjunction with the accompanying drawings, and its scope will be pointed out in the appended claims.